package com.onemile.controls;

import android.content.Context;
import android.graphics.Camera;
import android.graphics.Matrix;
import android.util.AttributeSet;
import android.view.View;
import android.view.animation.Transformation;
import android.widget.Gallery;
import android.widget.ImageView;

public class CstGallery3D extends Gallery
{
   private Camera mCamera = new Camera();// 相机类
   private int mMaxRotationAngle = 60;// 最大转动角度
   private int mMaxZoom = -300;// //最大缩放值
   private int mCoveflowCenter;// 半径值

   public CstGallery3D(Context context)
   {
	  super(context);
	  // 支持转换 ,执行getChildStaticTransformation方法
	  this.setStaticTransformationsEnabled(true);
   }

   public CstGallery3D(Context context, AttributeSet attrs)
   {
	  super(context, attrs);
	  this.setStaticTransformationsEnabled(true);
   }

   public CstGallery3D(Context context, AttributeSet attrs, int defStyle)
   {
	  super(context, attrs, defStyle);
	  this.setStaticTransformationsEnabled(true);
   }

   public int getMaxRotationAngle()
   {
	  return mMaxRotationAngle;
   }

   public void setMaxRotationAngle(int maxRotationAngle)
   {
	  mMaxRotationAngle = maxRotationAngle;
   }

   public int getMaxZoom()
   {
	  return mMaxZoom;
   }

   public void setMaxZoom(int maxZoom)
   {
	  mMaxZoom = maxZoom;
   }

   private int getCenterOfCoverflow()
   {
	  return (getWidth() - getPaddingLeft() - getPaddingRight()) / 2 + getPaddingLeft();
   }

   private static int getCenterOfView(View view)
   {
	  System.out.println("view left :" + view.getLeft());
	  System.out.println("view width :" + view.getWidth());
	  return view.getLeft() + view.getWidth() / 2;
   }

   // 控制gallery中每个图片的旋转(重写的gallery中方法)
   protected boolean getChildStaticTransformation(View child, Transformation t)
   {
	  // 取得当前子view的半径值
	  final int childCenter = getCenterOfView(child);
	  System.out.println("childCenter：" + childCenter);
	  final int childWidth = child.getWidth();
	  // 旋转角度
	  int rotationAngle = 0;
	  // 重置转换状态
	  t.clear();
	  // 设置转换类型
	  t.setTransformationType(Transformation.TYPE_MATRIX);
	  // 如果图片位于中心位置不需要进行旋转
	  if (childCenter == mCoveflowCenter)
	  {
		 transformImageBitmap((ImageView) child, t, 0);
	  }
	  else
	  {
		 // 根据图片在gallery中的位置来计算图片的旋转角度
		 rotationAngle = (int) (((float) (mCoveflowCenter - childCenter) / childWidth) * mMaxRotationAngle);
		 System.out.println("rotationAngle:" + rotationAngle);
		 // 如果旋转角度绝对值大于最大旋转角度返回（-mMaxRotationAngle或mMaxRotationAngle;）
		 if (Math.abs(rotationAngle) > mMaxRotationAngle)
		 {
			rotationAngle = (rotationAngle < 0) ? -mMaxRotationAngle : mMaxRotationAngle;
		 }
		 transformImageBitmap((ImageView) child, t, rotationAngle);
	  }
	  return true;
   }

   protected void onSizeChanged(int w, int h, int oldw, int oldh)
   {
	  mCoveflowCenter = getCenterOfCoverflow();
	  super.onSizeChanged(w, h, oldw, oldh);
   }

   private void transformImageBitmap(ImageView child, Transformation t, int rotationAngle)
   {
	  // 对效果进行保存
	  mCamera.save();
	  final Matrix imageMatrix = t.getMatrix();
	  // 图片高度
	  final int imageHeight = child.getLayoutParams().height;
	  // 图片宽度
	  final int imageWidth = child.getLayoutParams().width;

	  // 返回旋转角度的绝对值
	  final int rotation = Math.abs(rotationAngle);

	  // 在Z轴上正向移动camera的视角，实际效果为放大图片。
	  // 如果在Y轴上移动，则图片上下移动；X轴上对应图片左右移动。
	  mCamera.translate(0.0f, 0.0f, 100.0f);
	  // As the angle of the view gets less, zoom in
	  if (rotation < mMaxRotationAngle)
	  {
		 float zoomAmount = (float) (mMaxZoom + (rotation * 1.5));
		 mCamera.translate(0.0f, 0.0f, zoomAmount);
	  }
	  // 在Y轴上旋转，对应图片竖向向里翻转。
	  // 如果在X轴上旋转，则对应图片横向向里翻转。
	  mCamera.rotateY(rotationAngle);
	  mCamera.getMatrix(imageMatrix);
	  imageMatrix.preTranslate(-(imageWidth / 2), -(imageHeight / 2));
	  imageMatrix.postTranslate((imageWidth / 2), (imageHeight / 2));
	  mCamera.restore();
   }
}
